Currently, the Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology is evolving towards the TD-Long Term Evolution (TD-LTE) technology at an amazing speed in China, and application functions thereof are increasingly enhanced. As the 3G industry is being developed rapidly in China nowadays, the market for enhanced multimedia data cards is very promising.
Products currently developed support multi-mode applications such as TD-SCDMA/HSDPA/HSUPA/GSM/DCS, and also support multimedia broadcasting services. Because of the many comprehensive applications, the space in the layout and structural design of a printed circuit board (PCB) becomes much valuable for a data card; morover, data card terminals are now developing towards slim and compact profiles (e.g., towards a miniature profile or a USB-drive form). This imposes a hightened requirement on the PCB and the structural and layout design. However, during the development and design of the product, Joint Test Action Group (JTAG) and other necessary system status parameter monitoring points of ARM microprocessors (i.e., a series of microprocessors manufactured by Advanced RISC Machines Company) and Digital Signal Processing (DSP) microprocessors which are connected to a baseband chip of the data card are needed to be tracked and tested for the development of software and hardware as a new design application. Those test points usually amount to about 10, and this needs to occupy a sufficient space on the surface of the PCB of the data card to arrange the test points, which adds to the difficulty in achieving a compact layout of the PCB. Moreover, a window has to be formed in an enclosure of the data card so that, via the window of the enclosure, test clamps can be well positioned to make contact with the test points of the PCB within the enclosure. However, this not only makes the structural design of the PCB more complex but also has an adverse influence on the appearance of the data card, thereby significantly affecting the overall planning of the product as well as the competitive power of the product in the market.
China Patent Publication No. CN101458297Y discloses “TEST SYSTEM AND TEST METHOD FOR PCB”, according to which the PCB is tested by using test clamps to fix test points on the PCB and providing a window-like structure on an enclosure of a mobile phone. The aforesaid test process is very complicated. Moreover, before each of the test points is tested, the test point has to be re-positioned by using a corresponding test clamp, which increases the manufacturing cost and lowering the test efficiency. Accordingly, the prior art needs to be further improved.